<!DOCTYPE html>
<html lang="en">

<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document</title>
    <style>
        * {
            padding: 0;
            margin: 0;
            box-sizing: border-box;
        }

        .container {
            width: 1200px;
            margin: 0 auto;
        }

        .video video {
            width: 100%;
            padding: 20px 0;
        }

        .elevator {
            position: fixed;
            top: 280px;
            right: 20px;
            z-index: 999;
            background: #fff;
            border: 1px solid #e4e4e4;
            width: 60px;
        }

        .elevator a {
            display: block;
            padding: 10px;
            text-decoration: none;
            text-align: center;
            color: #999;
        }

        .elevator a.active {
            color: #1286ff;
        }

        .outline {
            padding-bottom: 300px;
        }
    </style>
</head>

<body>
    <div class="container">
        <div class="header">
            <a href="http://pip.itcast.cn">
                <img src="https://pip.itcast.cn/img/logo_v3.29b9ba72.png" alt="" />
            </a>
        </div>
        <div class="video">
            <video src="https://v.itheima.net/LapADhV6.mp4" controls></video>
        </div>
        <div class="elevator">
            <a href="javascript:;" data-ref="video">视频介绍</a>
            <a href="javascript:;" data-ref="intro">课程简介</a>
            <a href="javascript:;" data-ref="outline">评论列表</a>
        </div>
    </div>

    <script src="./lodash.min.js"></script>

    <script>
        const video = document.querySelector('video')
        //2.ontimeupdate事件触发时候，每隔一秒存一下当前时间
        video.ontimeupdate = _.throttle(function () {
            //2.1获取当前时间
            //    console.log(video.currentTime);
            //2-2 本地存储当前时间
            localStorage.setItem('currentTime', video.currentTime)
        }, 1000)

        //3 
        video.onloadeddata = () => {
            video.currentTime = localStorage.getItem('currentTime')
        }




    </script>

</body>

</html>